Typewriting machine



Dgc. 26, 1944.

v w. F.. HELMOND TYPEWRITING MACHINE Fild May 20, 1942 2 She ets-Sheet 2 R O T N E v m W/LL/AM F Hill/0ND BY I I ATTORNEY Patented Dec. 26,1944

UNITED STATES PATENT OFFICE 'rrrnwarrmo MACHINE William F. Heimond, Clinton, Conn., asslgnor to Underwood Elliott Fisher Company, New York, N. Y., a corporation of Delaware Application May 20, 1942, Serial No. 443,721

11 Claims.

driven parts within the machine, and, conversely, guards the motor-driven parts against injurious interference by the operator.

It is one of the objects of the invention to provide efficiently operative means which make it impossible to open such a cover while the ma-v chine is being motor driven.

It is a further object of the invention to provide reliably operative and simple means to make power operation of at least certain parts of the machine possible only in the closed position of said cover.

It is another object of the invention to provide means whereby energization of an electric motor is restricted to such times as the said cover is undisplacedl Still another object of the invention is to attain the said above objects by simple and reliably operative means which prevent closure of a motor switch when the said cover is open and which further prevent opening of the cover when the switch is open. i

The machine may be equipped with any suitable power carriage-return mechanism such, for example, as the one shown in the patent to Helmond No. 2,262,676, dated November 11, 1941.

Inasmuch as, according to the present invention, the motor or power drive of the machine is inoperative when the said cover is open, it follows that the carriage can only be power driven or power returned in the closed position of the cover. Stating it more specifically, regardless of what type of power-return mechanism may be employed, neither the operation of the carriagereturn key nor movement of the carriage toward line-end position can cause a power return of the carriage as long as the cover is in a displaced position. g

In many prior machines, as also in the one disclosed in the said patent 'to Helmond, a carriage return will ensue upon closure of the motor switch, if the carriage-return key or its equiv alent has been operated priorthereto. This is dangerous. to the operator and otherwise undesirable, and, in view of this, it is a further object of the invention to provide a power-moving mechanism for the carriage that can only be called into operation in response to controlling operations effected while the motor circuit or switch is closed.

Still another object of the invention is to provide that power-movements of the carriage can only ensue in response to operations of the controlling mechanlsm efi'ected after closure of the said cover.

Other objects and advantages of the invention will hereinafter appear.

In the drawings:

Figure 1 is a fractional perspective view of a typewriting machine embodying the invention and illustrating a normally locked displaceable cover unlocked due to the turning off of a power switch, the view also illustrating a carriage-return mechanism in a disabled condition.

Figure 2 is a fractional front view showing the power switch turned ofi and the cover opened; the power switch being incapable of being turned on pending restoration oi the cover to its closed position,

Figure 3 is a fractional front elevation showing the said cover restored and the power switch turned on,

Figure 4 shows a side elevation 01' the machine illustrating particularly a power typing mechanism and the aforesaid displaceable cover,

Figure 5 is a fractional front view of a portion of the carriage return mechanism, the mechanism being eflfectively conditioned.

Directing attention now to Figures 1 and 4, the typewriting machine may have an inner mechanism-supporting frame designated by the numeral II. This inner frame may rise from within a rectangular base frame H from which there also rises an outer frame or mask 13, concealing the inner'frame II. The mask l3 comprises opposite side walls I and a connecting front wall l5 having spaced shoulders l6 rising and curving rearwardly therefrom and blending into the side walls It. Covering the interior of themachine between the shoulders IE is a hingedly displaceable cover H which follows substantially the contour of the shoulders l6 and spreads laterally in a horizontal plane over two widely spaced ribbon spools indicated by dotted lines 2|. The portion 01' the cover I! between the said shoulders I6 is substantially coextensive with a nest of type-bar heads 22. The: cover has a finger piece [8 and is hinged upon pivot studs 23 projecting inwardly from the mask side-walls l4. When the cover I1 is displaced upwardly and rearwardly to the position indicated by the dotted lines in Figure 4, the interior'of the machine is conveniently accessible for such purposes as'cleaning 'the type heads and threading a typewriter ribbon into the machine.

Referring now for the moment more particularly to Figure 4, a platen carriage is guided for letter-feed and return movements in the conventional manner upon a trackway structure 25 which forms part of the inner frame The carriage has opposite end pieces 26 whereina platen 2.1 is revolvably supported. The aforementioned cover H, as may be, seen in Figure 4, extends closely to the platen. .The carriage is fed in letter-feed steps by a letter-feed spring, not shown, under the control of a conventional escapement, in a manner well known.

An electric motor 28 disposed at the left rear portion of the machine, seeFigure 1, provides the motive'power for returning the carriage and operating the typing instrumentalities. Since the carriage-return mechanism shown agrees with the one of the said patent to Helmond, it will be necessary only todescribe it briefly. Extending rightwardly from the motor is a shaft 3| provided with pinion teeth 32 meshing with a gear 33, the latter being fixed on a spindle 34. A frame-supported housing 35 provides journals for the right end of the'shaft 3| as well as for the spindle 34. A flanged drum 36 is normally rotatably loose on the spindle 34, anda draw band 31 is so attached to the said pulley as to be wound thereupon when the pulley is rotated counterclockwise of Figure 1. During use of the machine, the motor 28 rotates the gear 33 and spindle 34 continuously, but not the drum 36. Said gear has clutch teeth 38, and the pulley 36 has splined thereto a toothed clutch collar 4| which is rotatably loose on thespi'ndle 34, but axially movable therealong from an open-clutch position to a position in which it is clutched to the said gear 33. A rock shaft 42,fjournalled in 'the casing 35, has fixed thereto a yoke 43 disposed in a groove in the clutch collar 4|. An operating arm 44, fixed to the shaft 42, serves to rock said shaft and its yoke to movethe clutch collar 4| to close and open the clutch, The draw band 31 passes over guide pulleys 45 and 46, onto a pulley 41 joumaled on the left carriage end 26 and has 'an end so attached to and wound around the pulley 41 that rightward pull on the draw band will rotate the pulley clockwise. Fixed to and rotatable with said pulley is a bevel pinion 48 in constant mesh with a bevel gearsector relatively mounted on the left carriage end 26. Said sector 5| is integral with a cam 52 for actuating a spring returned line-space lever 53 carrying a line-space pawl 64, the latter, when actuated, feeding a toothed line-spacing wheel 52 being unitarily revolvable 'with the platen 21. actuation of the line-space lever 53 OCC11IS upon the rightward pull of the draw band 31 resulting from an engagement of the clutch member 4| with the clutch teeth 38. Following the conclusion of the power carriage return, in a manner to be hereinafter described, a spring 56 returns the ing the restoring spring 56 of the said sector 5|.

A link 62 providesan operative connection be- The tween said arm 44 and arm 63 of a lever 64, the latter being pivoted at 65 to the machine framework and being normally restrained against clutch closing movement by a latch hook 66 of a pivoted lever 61. It will thus be seen that with said lever arm 63 normally latched, a spring 6| acting upon the arm 44 is normally restrained from closing the carriage-return clutch 38, 4|. When it is desired to power-return the carriage, the operator effects an operation of a pivoted, spring-restored carriage-return lever 68, by depression of its key 1|. This results in an actuation of the latch lever 61 which releases the lever 64 to the clutch closing action of the spring 6|. The motor-driven rotation of the pulley 36 resulting from the closure of the clutch 38, 4|, drives the carriage-carried pulley 41 and results first in the actuation of. the line-spacing mechanism 53, 54. After a limited actuation of the line-spacing mechanism and consequentlya limited rotative movement of the pulley 41, the band 31 picks up the carriage to effect its return.

The lever 64 is automatically restored to the control of the latch hook, at a' predetermined pointin the return of the carriage, responsive to the engagement of a margin stop 12 with a counterstop 13, the resulting effect being the disconnection of the'clutch collar 4| from the clutch V teeth 38 on the gear '33. Thedetails, by means of which the lever 64 may be restored, are shown' in the said patent to Helmond and their description and illustration arenot deemed necessary for an understanding of the invention.

The latch lever 61, normally retaining, the i lever 64 against clutch-closing operation, has

ivotally mounted thereon, and yieldingly operable thereby, a secondary latch 14, the latter beingadapted to hold the arm 63 slightly lower than the latch hook 66 is capable of doing. Nor

mally, however, this secondary latch is held out of cooperative range with the arm 63 by the upper end of the latch hook 66. Upon-depression of sumciently far so'that the secondary latch 14 will move over the arm 63, providing the carriagereturn key is still depressed. In any event, the latch hook 66 will be in. control of thelever 64 after the release of the carriage retum-key.

Referring now again more particularly to Figure 4,- type bars 16 are pivotally mounted in a semi-circular array, the aforementioned heads 22 of the bars being nested on a curved rest 11. The type bars may be power-actuated inthe manner shown and described in the, patent to Yaeger No. 2,254,764, dated September 2, '1941. Describing the power mechanism of this patent briefly, each type bar 16 has a link connection 18 with an upright sub-lever 8| which has a pendant arm 82 in rolling contact therewith. Connected to each arm 82 is an actuator 83 having its rear end urged upwardly and rearwardly against a bar 84 by a spring 85. The rear ends of theactuators 83 are adapted to be selectively drawn.

down to engage the snatch teeth with a toothed power shaft 81, under the control of type keys 88, the latter being on the front ends of springrestored key levers 9| carrying hook-shaped members Blwhereby to draw the actuators downwardly. During use of the machine, the saidj power shaft 81 is driven by the spindle 34 through a belt drive as. and any actuator drawn into engagexn'ent with said toothed power shaft 01 will be operated by the latter, wherefore the type bar corresponding to the operated actuator will type.

In the circuit of the electric motor 20 is a tumbier or snap switch 94 of standard manufacture. secured to a'bracket or ear 9! of the machine frame II. The tumbler'switch has an operating arm 96 which is operable from the front of the machine by a. control knob 91 through connections presently to be described. The knob 91 is fast upon a stub shaft 98 protruding from and I, pivoted in another ear I04 of the mechanism The rear end of the crank supporting frame II. shaft carries fixedly a plate I provided with a stud I 06 into a socket of which the switch arm 98 extends. Turning'the knob 81 from the position of Figure 1 to the position of Figure 3 closes the tumbler switch 94. It may be noted at this point that the connection; of the crank I02 with the disc IN is such that the mask I3 may be removed readily from the inner frame III. The plate I05 has articulated to an ear I01 thereon a rightwardly extending rod I08 which near its right end is slidinglyguided in a perforation I09 provided on a fixture II 0. A right-angularly bent-off right and III of the rod overlies the arm 63 of the clutch-controlling lever 64 and is guided in a laterally disposed slot II2,'of a bracket H3, the latter being rigidly secured to the said fixture IIO. With the switch mechanism in the turnedoff position, as in Figure 1, the rod end III exerts such control over the lever 64 that the right extremity of the arm 63 is held lower than the latch shoulder of both the latches 6B and 14. Should the switch mechanism, therefore, be turned off when the carriage-return key II is depressed, no carriage return will ensue unless the carriagereturn key is reoperated after the switch mechanism has been turned on. In other words, no I dangerous surprise movements by the carriage are possible due to an unauthorized or accidental operation of the carriage-returnkey 1i while the r switch mechanism is turned off. It is here to be understood that under any condition, subsequent to the closure of the switch, the lever 64 will always be held by one of the latches 66 or I4 and that only a subsequent operation of the lever 61, as by the key II, will be effective to cause closure of the clutch and consequently a power movement, of the carriage. If, therefore, the switch should be opened while a carriage return movement is incomplete, the, carriage will not be power-moved upon subsequent closure of the switch, except if followed by a new operation of the lever 61. It should here be observed that the left endof the slot wherein the rod end I I I is situated, see Figures 1 and 5, is parallel with the adjacent portion of the lever 64 and prevents the lever '64 from exerting any force'onthe rod I08 which would tend to close the tumbler switch In order to suppress or prevent opening of the cover I1, when the switch is turned on as illustrated in Figure 3, there is provided a lock lever II4 which, in the closed position of the cover,

hasan end II5 situated in a. yoke H6. The lever Ii 4 is pivoted upon the interior of the mask at II! and has a ieftwardly extending arm III which, in the turned-on position of the switch. is blocked. against clockwise displacement by a dwell I2l on the disc IOI. Consequently, when the switch is turned on as in Figure 8, it is impossible to open the cover; The disc IOI is so formed that in the open position of the switch the lever arm IIO has considerable capacity for movement toward the stub shaft as (see Figure 1); the disc l0I having a sharp drop-off or shoulder I22 adapted to cooperate with the lock arm ,I I 8 to prevent turning on of the switch when the arm is swung towards the stub shaft 98. The pivot axis of the cover is at a higher location than the yoke H6, and, consequently, the cover,

in being displaced, swings initially in a forwardly inclined arc. During such initial displacement,

the cover rocks the lock lever H4 in counterclockwise direction and thereby causes the arm II8 thereof to swing into switch-locking relation with the shoulder I22. After some displacement of the cover, the yoke H6 swings clear of the lever end H5; and from then on, pending the restoration of the cover, the lever I I8 will remain in switch-locking position under the tension of a spring I24, wherefore power-typing and carriage-retuming operations can only be effectedwhen the cover is closed, and wherefore'to call a power-return of the carriage into operation the cover must always be closed first, 0

With the carriage substantially centered, the cover I1 is displaceable to the position illustrated in dot-and-dash lines in Figure 4, that is, the wide portion of the cover is then located between the front portions of the opposite carriage ends 26, in a position obstructing carriage movement. However, no harm can come'of this, since the carriage-return mechanism is then completely disabled.

In swinging the cover to normal position. the shorter prong I25 of the yoke passes in front of the lever end II5, whereas the longer prong I26 engages and actuates the latch lever II4. While the lever H4 is being actuated, the yoke IIO swings rearwardly and downwardly about the cover, pivot pins 23 until the lever end III is fully between the said prongs, as seen in Figures 1 and 4, the knob 91 being then operable to close the motor circuit and enable carriage-return mechanism. The weight of the cover Ill is sumcient to-overcome the tendency of the spring I24 to lift the cover. However, detents I21 may be provided to hold the cover more securely in closed position. The lever I I4, to prevent its end H5 from flexing in a fore-and-aft direction, may have a firm guiding support near the said end, as indicated at I28. r

While the invention has been described with reference to the details shown in the drawings, it is not restricted to the particular construction or method of operation set forth. The scope of carriage, comprising, an electric in the following motor, control means operable to close said drive connection, wherefore. if said switch is: closed, operation of said control means causes saidcarriage to be power driven, and means responsive to opening said switch to render said drive con nection open if it has previously been closed.

. to opening said switch to render said drive connection open and/ or to suppress closure of said 7 drive connection by said control means.

3. In a twpewriting machine having a carriage, normally disabled power-driving means for said carriage, comprising, an electric motor and anormally open clutch, a switch to energize and deenergize said motor, means movable to open and close said clutch, biased to close it, means adapted to hold said biased means after clutch opening movement, being operable to release said biased means for effecting closure of said clutch, and means so controlled by said switch that in response to motor deenergizing operation of said switch the said biased means is moved to open said clutch, said holding means including a provision whereby upon clutch-opening movement it will hold said biased means pending a new releasing operation. a

4. In a typewriting machine having a carriage, power-driving means for said carriage, comprising, a normally open drive for said carriage, a

cover displaceably mounted to uncover parts of the machine, and mean to close and op n said drive, including means so controlled by the position of said cover that said drive can only be in a closed state when said cover is substantially closed. V

5. In a typewriting machine having a carriage, power-driving means for said carriage, comprising, a motor, and a normally open drive for said carriage, a cover displaceably mounted to uncover parts of the machine, means for closing and opening said drive, including means operable to render said drive open, and means so associating said cover with said rendering means as to compel the drive to be open whenever the cover is displaced.

6. In a typewriting machine having a carriage, power-driving means for said carriage, comprising, a normally open drive for said carriage, a cover displaceably mounted to uncover parts of the machineand control means to open and close said drive, including means operable to one position to lock said cover, and operable to another position to unlock said cover and open said drive,

said last means including a provision whereby it will be locked in said other position whenever the said cover is opened, whereby said cover can never be opened when said drive is closed, and whereby when said cover is opened the'said drive cannot be closed.

'7. ma typewriting machine having a cover displaceably mounted for uncovering parts of the machine, normally disabled power-driving means for said carriage, comprising, an electric motor and a normally open drive from the motor to the carriage, a switch to energize and deenergize said motor, means operable to close said drive, switch opening and closing means so controlled by the position of said cover that whenever said cover is open said switch must also be open, means to open said drive concomitantly with opening said switch, said last means being incapable of closing said drive, and means requiring said operable means to be operated in the closed position of said switch in order to eflect closure of said clutch.

moved to said closed switch position, and means,

means following closure of said switch, a cover displaceably mounted to uncover "parts of the machine, and means adapted to render said cover undisplaceable while the motor is energized and adapted" throughdisplacement of said cover to lock said switch against motor energizingoper- 'ation, wherefore, said driv connection cannot be closed by operation of said control means, exa cent when the cover is.closed.

9. In a typewriting machine having an electric motor for driving. parts thereof, a cover displaceably mounted to uncover parts of the machine, av snap switch for said motor,. including control means operable alternatively with a snapping-action to a definitely defined open and to a definitely defined closed switch position, means operatively connected with said control means' for concomitant operation therewith, and means governed by said cover in a manner to receive a positive movement therefrom during initial cover displacement and to return to original position during cover closure, said connected means and said governed means being devised for such cooperation, that the connected meansin the said defined closed switch position blocks said governed means against reception of the said positive movement, and that upon receipt of said positive movement, said governed means blocks said connected means in the said defined closed switch position, wherefore the cover is only displaceable when the switch is open, and wherefore th switch can only be closed when the cover is closed.

10, In a typewriting machine having an electric motor for driving parts thereof, a cover hingedly vdisplaceable in a wide are on th machine, a switch for said motor, including control means operable alternatively to a'deflnitely defined open and to a definitely defined closed switch position, means operatively connected with said control means for concomitant operation therewith, means supported independently of said cover and operable to block said connected means so as to block switch closing operation of said control means from said defined open switch position, said connected means being devised to obstruct operation of said independently sup- P rted means whenever said control means is to operate and restore said independently supported means respectively by displacement, and

restoration of said cover, comprising a normally established operating connection between a wide swinging part of said cover and said independently supported means, said connection being of a nature to become automatically severed after an initial cover displacement and to become automatically reestablished towards the nd of the closing movement of the cover.

11. In a typewriting machine having a carriage normally disabled power-driving means fpr said carriage, comprising, an electric motor and a normally open drive connection from said motor to said carriage, circuit opening and closing means, control means operable to clnse said drive connection, so that if said circuit is in a closed condition, operation of said control means will caus th carriage to be power driven, and means responsive to circuit opening by said circuit opening means, to render said drive connection open it it has previously been closed, said responsive means including means devised to suppress upon response the closure of said drive connection by operation of said control means unless the circuit is first closed again and the control means operated subsequently to such circuit closure.

WILLIAM F. I'IELMDND. 

